From: Yuan Can yuancan@huawei.com
[ Upstream commit 98af0a33c1101c29b3ce4f0cf4715fd927c717f9 ]
A problem about ntb_hw_amd create debugfs failed is triggered with the following log given:
[ 618.431232] AMD(R) PCI-E Non-Transparent Bridge Driver 1.0 [ 618.433284] debugfs: Directory 'ntb_hw_amd' with parent '/' already present!
The reason is that amd_ntb_pci_driver_init() returns pci_register_driver() directly without checking its return value, if pci_register_driver() failed, it returns without destroy the newly created debugfs, resulting the debugfs of ntb_hw_amd can never be created later.
amd_ntb_pci_driver_init() debugfs_create_dir() # create debugfs directory pci_register_driver() driver_register() bus_add_driver() priv = kzalloc(...) # OOM happened # return without destroy debugfs directory
Fix by removing debugfs when pci_register_driver() returns error.
Fixes: a1b3695820aa ("NTB: Add support for AMD PCI-Express Non-Transparent Bridge") Signed-off-by: Yuan Can yuancan@huawei.com Signed-off-by: Jon Mason jdmason@kudzu.us Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ntb/hw/amd/ntb_hw_amd.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/ntb/hw/amd/ntb_hw_amd.c b/drivers/ntb/hw/amd/ntb_hw_amd.c index 0b1fbb5dba9b6..7de7616803935 100644 --- a/drivers/ntb/hw/amd/ntb_hw_amd.c +++ b/drivers/ntb/hw/amd/ntb_hw_amd.c @@ -1139,12 +1139,17 @@ static struct pci_driver amd_ntb_pci_driver = {
static int __init amd_ntb_pci_driver_init(void) { + int ret; pr_info("%s %s\n", NTB_DESC, NTB_VER);
if (debugfs_initialized()) debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
- return pci_register_driver(&amd_ntb_pci_driver); + ret = pci_register_driver(&amd_ntb_pci_driver); + if (ret) + debugfs_remove_recursive(debugfs_dir); + + return ret; } module_init(amd_ntb_pci_driver_init);